MULTIGENERATIONAL AMPLIFICATION OF A REFERENCE LADDER FOR ALLELES AT LOCUS D1S80

The interlaboratory typing of DNA specimens that have been amplified a t the D1S80 locus necessitates the use of a standard allelic reference ladder. This communication describes a technique in which individual, amplified alleles are isolated, combined, and amplified by PCR to pro duce a functional reference ladder composed of many of the alleles tha t occur at this locus. The amplified ladder can serve directly as a te mplate source for production of the next generation of reference ladde r. This process, in which each amplified ladder serves as the template for the next has been carried through multiple generations.